Automatic electric heater.



L. S. BESLEY.

AUTOMATIC ELECTRIC HEATER.

APPLIGATION FILED SEPT. 26,'1911.

Patented Feb. 11, 1913.

l i"s UNITED sTATEs PATENT oEEIoE.

LEWIS s. B EsLEY, or sALT LAKE CITY, UTAH.

AUTOMATIC ELECTRIC HEATER.

. Specication of Letters Patent. y

Patented Feb. 11, 1913.

Application led'September 26, 19'11. Serial No. 651,420.

To all whom t may concern.' A

Be it known that I,`LEwIs S. BEsLEY, citizen of t-he United States,residing at Salt Lake City, in the county of Salt Lake and State ofUtah, have invented certain new and useful Improvements in AutomaticElectric Heaters, of which the .following is a specification.

My invention relates toelectric heaters, and particularly to a heateradapted to be attachedl to an ordinary electric light wire vand adaptedto be used as a bed warmer or as a means of otherwise applying heatlocally. t

The primary object of my invention is to provide a very convenient,simple and effectained within a casing shall act to break the circuitthrough the heating coils when the temperature of the heater has arrivedat any desired point.

A. further object' is to provide means whereby the air may be compressedto a greater' or less degree so as to permit the heater to be raised tovarious temperatures before the circuit through'the heating coils isbroken. y

Another object is to provide means whereby the circuit through theheating coils shall `be broken when the temperature rises to a dangerousdegree.

Other objects will appear in the course of the following description.

My invention is illustrated in the accompanying drawings wherein: y

Figure 1 is a perspective view of my improved heater. Fig. 2 is alongitudinal section of the heater, on the line 2-*2 of Fig. 3. Fig. 3is a transverse section of the heater on the line 3 3 of Fig. 2.

Corresponding and like parts are referred to in the followingdescription and indicated in all the views of the accompanying.drawsvings by the samel reference characters.

Referrin to these drawings, 2 designates a casing o any desired shapebut shown as cylindrical. This casing is preferably made of metaland iscovered by any suitable in` sulation designated 3. I do not wish tolimit myself to any part-icular'insulation or any particularA means forinsulating vthe casing. Ig' have shown it as covered with a layer ofinsulating paint or enamel. This V ca ing is closed at oneend by meansof a pl te or end piece having therein a spring section 4 of Aresilientmetal and operating very much after the manner of the bottom of an oilcan.,

The opposite end of the casing 2 is closed and provided with a plug orbase such as used `in electric lighting. flDreferably the centralterminal 5 of thls plug or base is electrically connected to a wire 6which eX- tends 4from thel terminal 5 .throughl suitable insulation 7 tothe interior ofthe casing. The exterior of the plug is of course formedwith a screw threaded brass sleeve 8 which is in electrical connectionwit-hthe metal forming the casing 2.

Supported 1n any sultable manner within the casing 2 is a mandrel or rod9 which may be of any suitable material and `is preferably, though notnecessarily, tubular so as to make it light. This rod 9 may be ofinsulating material, or it may be oit' non-insulating material coveredwith insulation.`

In the illustration of my invention herewith given, the Amandrel 9 iscovered with insulating 1naterial, 10. As illustrated, the mandrel 9is'supported at one end by projecting through the cap l1 which closesone endy of the casing 2, and the other end of the mandrel is supportedby means of a suit-ably insulated spider 12.

' Wrapped upon the mandrel overthe insulation thereof is a wire formingthe heating coils 13. This spirally wrapped wire extends from one end ofthe mandrel to the other, except that a small space is left at each endofthe mandrel. The wire forming the coils 13 at one end is connected toa band 14 of copper or like material to which the wire G is electricallyconnected. The other end of the wire forming the heating coils 13 iselectrically connected lto. a band 15 of copper or like material.

Projecting from the end of the mandrel toward the resilient end piece 4is a contactpin 1G which is .electrically connected by the wire 17 tothe copper ring 15. The extremity of this pin 16 is normally in contact.with the resilient end piece 4 but the resilientI end 4piece iscapableofl springing lout and away from the end of the'pin 16,

thus breaking the circuit through the heating coils ,13.

So far as described, the operationo my improved heater is as 'ollowszThe plug carried upon the end of the casing is con` nected to anelectric light socket (not shown). The current from the wire `con-'nested to the socket passes through the terf back through the supplywire. The passage of the current through the heating coils 13 will raisethe temperature of these coils, and this in tul'n will raise thetemperature of the air contained within the casing 2. The airL-withinthe casing expands under the action of therheat, and eventually it willovercome the resilience of the spring end piece 4 and the end piece willspring outward under the pressure of the air, thus breaking the circuitthrough the heating coils. `When the temperature falls to such a'.degree that the-air within the casing 2 contracts beyond a certainpoint, the resilience of the end piece 4: will cause it to spring inwardand into contact with the terminal 16, thus again establishing a circuitthrough the coils. Thus the action of the device is automa-tic just solong as it is connected in circuit with the source of supply.

Tt will be obvious /that the temperature required to expand the aircontained within the casing, 2 so as to actuate the spring end piece 1will depend upon the original pressure of the air within the casing 2,and for the purpose of varying this pressure and thereby varying thedegree oi' heat to which the coils are raised before the circuit isbroken, T provide means whereby the air within' the casing 2 .may becompressed to any desired degree. For this purpose T have provided anair inlet tube 18 which projects into the casing and preferably iscarried upon the end piece 11. This air inlet tube is precisely the sameas the air inlet tube ordinarily used on pneumatic tires, though T donot wish to be limited to this precise construction. Tt is provided withthe internal valve 19 which opens upon pressure from the outside andcloses upon pressure from the inside of the casing. Tt is preferablyprovided with a cap 20 which is removable to permit the vair inlet tubeto be connected to any suitable air compressing means such as a bicyclepump.

noaaeee With this construction, the air may be rst compressed within thecasing 2 to any desired degree and then the current turned on. Tt willbe obvious that a certain degree of pressure of the air has already beensecured by means of this compression. Hence a less degree of heat willbe required to expand the air suiliciently to spring outward ythe endpiece 4f than' if the air were not compressed. Inasmuch as, however, itis diflicultto regulate the degree of compression so as to secure abreakingQ the circuit through the heating coils when a certaintemperature has been attained,v T preferably r-st turn the currentthrough the heating coils until the heater has been raised to the propertemperature. Then air is pumped in until the end piece 4 snaps outward.This compression of the air breaks the circuit through the heating coilsat the proper degree of heat, and when the temperature of thiscompressed air is lowered by the. breaking vot the circuit, then thespring end 4: will spring inward, again making contact with the pin 16.The temperature will thus b-e kept automatically at the predetermineddegree.

llt will be obvious that the resilient end piece 4 constitutes aresilienty diaphragm which is forced in one direction by the compressionof air within the casing and is returned to its original position upon adecrease in this pressure within the casing by the resiliency of thediaphragm. Vihile T have illustrated this diaphragm. as' itorming theend of the casing, it is to be understood that the diaphragm might belocated intermediate of the ends of the casing and still perform vitsfunction in practically the same manner as described..

In order to prevent'a too high amount of current from passing into theheater, T preferably provide a fuse 21. This fuse is secured by makingthe connection 17 of resilient wire 'which .tends to spring outward andaway from the copper band 15. This wire 17 is held in cont-act'with theband 15 by easily fusible solder.. When the. temperature is raised toohigh, this solder will'l fuse 'and the wire 17 willspring outward, thusentirely breaking the circuit.' Tt will be understood that fused plu sor like devices might be used for brea 'ng this cir-v cuit upon theburning out of the fuse.

While T haveillustrated what T believe to be the best and most effectivearrangement of my invention, T do not-wish to be limited to the detailsof the arrangement or the,y details of the construction as it isobvionsjthat the device might bemodiied in many vvvlfays withoutdeparting from the spirit of the '1nvention. My invention is simple, canbe cheaply made and is thoroughly edective in use.

Whileil have described this device as bene v ing used with air alone asa filling for the casing, it is to be understood that I may'also use oilor like liquid within the casing together with air, the air being usedto secure thei elasticity necessary to operate the spring en Thesnapping of the spring is a very vital and important part of myinvention as without it the contacts would spark and would soon burnout.

It Will be obvious that the principle of my device may be applied to alarge number of other devices than mere electric heaters and that it maybe used wherever it is desired to cause a'circuitto break when a certaintemperature has been reached.

What I claim is:

1. A11 electric heater including in. its orlor decreased.

2. An electrical heater including in its organization an outer casing,an end plate closing one end of the casing and aresiliently' deformablediaphragm closing the other end of the casing, a mandrel supportedwithinth'e casing andextending the whole length thereof, an electrical heatingcoil mounted upon said mandrel and insulated therefrom, afplug passinthrough the end ofthe casing opposite the iaphragtrr, said plugincluding a central contact and an exterior contact sleeve, a connectionbetween the heating coil and the central contact of the plug, a rigidcontact pin carried by the mandrel opposed to said iaphragm and normallyin contact therewith, and means whereby fluid expansible under heatmaybe initially compressed within the casing.

3. An electric heater including in its or- Vganizati'o-n an outercasing, electricheatingh thereof, said diaphragm'being movable intocoils inclosed-within the casing andconnected in circuit with a sourceof energy, thermostatic means for breaking the circuit when thetemperature within the casing has risen above a predetermined point andformaking 'p said circuit when the temperature therein has lowered belowa predetermined oint,

said means including a member mova le in one directionby an increase of`pressure of the fluid contained within the casing and movable in anopposite direction by the decrease of pressure in said fluid, and afluid pump connected to said ,casing for the purelng pose ofl adjustablyvarying the fluid pressure within the casing.

4. An electric heater including in its organization anouter casinghaving an inlet opening, electric heating coils inclosed Within thecasing and connected in circuit with a source of energy, andthermostatic means :for breaking the circuit through said coils when thetemperature within the casing has risen above a predetermined point andfor making said circuit when the temperature therein has lowered below apredetermined point, said means including a member movable in onedirection by an increase of pressure within the casing consequent upon arise in temperature above a predetermined point and movable in the otherdirection by a decrease of pressure. within the casing consequent upon adecrease of temperature, and a pump detachably engaging the inletopening of the casing.

5. An electric heater, including inits organization an outer casinhaving an' inlet opening, an inwardly opening valve disposed in saidopening, said opening being provided with a screw-threaded nipplewhereby it may be connected to fluid compressing devices, electricheating coils inclosed'within the casingand connected-in circuit with asource of energy, thermostatic means for breaking the-circuit throughsaid coils when the temperature within the casing has risen above apredetermined point, and for making the said circuit when thetemperature therein hasy lowered below a predetermined point, said meansincluding a member movable in one direction by an increase of pressurewithin the casing consequent upon a rise in temperature, and movable inthe other direc- -casing and the other electrically connected to thecoil, and a diaphragm voperatively mounted upon saidcasing and formingpart and out of electrical engagement with one terminal of said coil tomake or break the circuit .therethrough and through the casing, saiddiaphragm being actuated in one or the other direction by increase ordecrease of pressure within the casing.

In testimony whereof I aix my signa- 1 ture in presence of twowitnesses.

' LEWIS S. BESLEY. [1.. a]l Witnesses:

' SNUEOEN,

S. ANDREW JACKSON.

